build(rk3568): add build configs for rk3568

This is needed to support compiling new source file.
Also updated the default tf-a build configs for rk3568.

Signed-off-by: shengfei Xu <xsf@rock-chips.com>
Change-Id: I3ee2c1f64e65d76bdfcf262d28122c11cdf7c9c8
5 files changed